Oral Path Quiz 1

Front 1

Dentigerous Cyst characteristics and diagnosis

Back 1

aka Follicular cyst
- Derived from the REE either in between two layers or between the IEE and tooth
- Most often occurs in Mandibular 3rd molars, Maxillary canines and 3rd molars, and Mandibular second premolars in young adults
- Atleatst 4mm of radiolucency is necessary to differentiate a Dentigerous cyst from an enlarged follicle

Front 2

Dentigerous cyst Histology

Back 2

- Cyst wall is composed of fibrous connective tissue lined by epithelium
- Non inflammed cysts are lined by a thin non-keratinized epithelium resembling the REE
- With inflammation, epithelium is thickened and more proliferative. Often, epithelium shows up in the connective tissue
- May present with nodular thickening which can represent a neoplastic change

Front 3

Eruption Cyst characteristics, treatment, and Histology

Back 3

- A Soft tissue Dentigerous cyst seen in the soft tissue directly overlying the alveolus of an eruption tooth. Most often on Permanent 1st molars and Maxillary incisors.
- Most commonly seen in children and may present as a fluctuant swelling but may be dark red when filled with blood due to hematoma
- Simple excision of roof usually results in tooth eruption
- Histology shows epithelial lining cyst cavity, and a surface mucosal epithelium which is the roof exposed to the oral cavity

Front 4

Odontogenic Keratocyst characteristics

Back 4

*-Male Predicament, with Mandibular body/ramus twice as common as maxilla
- Derived from dental lamina or a normal/supernumerary tooth before hard tissue formation
- Presents as a well defined unilocular or multilocular radiolucencies with scalloped or smooth borders. Often produce cortical expansion with tooth displacement/resorption

Front 5

Odontogenic Keratocyst histology

Back 5

Cyst has a thick, non-inflammed connective tissue wall lined by a univorm stratified squamous epithelium
- Surface has a wavy or corrugated appearance and is typically covered by parakeratin.
- Also shows palisaded nuclei which may be lost during significant inflammation in the CT
- Has a definite aggressive potential. Although a cyst, recurrence is frequent due to presence of daughter cysts and the friable nature of cyst wall. 30% recurrence as late as 10 years after initial surgery

Front 6

Orthokeratinized Odontogenic Cyst characteristics and histology

Back 6

Also Male predicament with Mandible twice as common
- Usually well defined unilocular
- When orthokeratin covers the odontogenic cyst instead of parakeratin
- Less aggressive and have a much lower rate of recurrence
- No nuclei present in keratin layer and basal cell layer is less prominent with a more flattened or squamous appearance compared to parakeratotic type

Front 7

Basal Cell Nevus Syndrome characteristics

Back 7

aka Gorlin-Goltz Syndrome
- Autosomal Dominant Hereditary syndrome due to loss of tumor supressor PTCH on chromosome 9
- Multiple odontogenic keratocysts of jaws
- Cutaneous abnormalities including multiple basal cell carcinomas, palmar/plantar pitting, and epidermal cysts
- Skeletal anomalies

Front 8

Lateral periodontal cyst characteristics and histology

Back 8

Mostly a disease of the 5th-7th decade mostly occuring in mandibular Lateral, Canine, Premolar area with a well defined radiolucency
- Occurs on the lateral aspect or between the roots of VITAL teeth
- Usually asymptomatic and comprises of only 2% of intraloral cysts. Diagnosis only made once keratocysts are ruled out
- Histologically, cysts are lined by a thin, non-keratinizing squamous or cuboidal epithelium. May have localized epithelial plaques or thickenings
- Must be differentiated from a lateral radicular cysts which is associated with a non-vital tooth and is inflammatory in origin

Front 9

Botryoid odontogenic cyst

Back 9

Multilocular variant of the lateral periodontal cyst

Front 10

Gingival cysts of adults characteristics and Histology

Back 10

Uncommon and appear as small soft tissue swellings in the attached gingiva or interdental papilla
- Commonly involves mandible especially in the canine and premolar region
- May assume bluish discoloration
- Histology is similar to a lateral periodontal cyst with focal plaque-like thickenings

Front 11

Gingival (Alveolar) and Palatal Cysts of the Newborn characteristics, histology and treatment

Back 11

- Focal white nodules in the alveolar ridge mucosa, Medial palatal raphe, or at the junction of hard/soft palate
- All of which represent Keratin (Inclusion) Cysts
- Histology shows small superficial cysts containing Keratin debries lined by thin parakeratinized stratified squamous epithelium
- No treatment necessary since they spontaneous rupture within a few weeks after birth

Front 12

Calcifying Odontogenic Cyst characteristics and Histology

Back 12

COC
- Mostly in the incisor/canine area
- Appears as well defined radiolucency with radiopaque structures within the lesion
- Histology shows Polarized basal cell composed of columnar or cuboidal cells with characteristic keratinized "Ghost" epithelial cells containing eosinophilic cytoplasm

Front 13

Radicular cyst and Apical granuloma general characteristics and histology

Back 13

Radicular cyst is the most common cyst found in jaws and is inflammatory in origin
- Most common in anterior maxilla
- Derived from epithelial rests of Malassez in the PDL after pulpal inflammation spreads to the periapical area forming an apical granuloma
- Diagnosis of radicular cyst can only be made if an epithelial lining is present
- Consists of inflamed granulation tissue surrounded by a fibrous connective tissue wall

Front 14

Radicular cysts

Back 14

Can be found on any tooth, but a non-vital maxillary lateral incisor is most common
- Characteristic findings are hyaline bodies, foam cells and cholesterol clefts within the connective tissue wall
- Contains many inflammatory cells composed of lymphocytes and plasma cells. Russel bodies which are eosinophilic immunoglobulin granules are often found in the connective tissue matrix.

- Diagnosis is accomplished thorough histology combined with clinica (non-vital) and radiographic (PA lucency) features

Front 15

Apical scar

Back 15

Usually occurs in anterior maxilla and occurs when periapical inflammation is filled with fibrous tissue rather than bone
- Clinically, tooth is asymptomatic and radiolucency is discovered on routine examination
- Usually a history of periapical lesion and root canal filling and apical currettage
- Characterized by circumscribed radiolucency at the tooth apex

Front 16

Developmental cysts

Back 16

Termed developmental because they are thought to arise from epithelial remnants trapped along lines of embryonic fusion

Front 17

Nasopalatine Duct Cyst characteristics and histology

Back 17

Most common Non-odontogenic cyst of oral cavity
- Usually occurs in late adults in the anterior midline palate
- Can occur in the epithelial remnants of the nasopalatine duct that persist in adults
- Appears as a well circumscribed or heart shaped radiolucency near midline between and apical to central incisors
- Histology may show a fibrous connective tissue wall containing large nerves and vessels

**Contast with a Nasopalatine cyst which is a soft tissue cyst of the incisive papilla region

Front 18

Globulomaxillary cyst

Back 18

Found as an inverted pear-shaped radiolucency in maxilla between lateral incisor and canine
- Considered odontogenic in origin and frequently lateral periodontal cysts

Front 19

Nasolabial/Nasoalveolar cyst

Back 19

Non-odontogenic soft tissue cyst with a FEMALE predicament
- Cyst located at base of nostril producing a swelling under the upper lip in canine region/Nasal floor
- Usually does not show radiolucencies but does appear off to one side of midline
- Lined by ciliated or nonciliated pseudostratified columnar epithelium with abundant mucous cells

Front 20

Traumatic/Solitary Bone cyst characteristics

Back 20

Male predicament more commonly in the mandibular body/symphesis
- Radiolucency extends between roots of teeth and has scalloped outline
- Pathogenesis is unknown, and the "cyst" is a large empty cavity in bone or containing a small amount of fluid
*- Not a true cyst so no epithelium is seen

Front 21

Aneurysmal Bone cyst characteristics

Back 21

Generally occurs in individuals under 30 in posterior regions of mandible
- Capillary-venous malformation within bone
- May rapidly increase in size and cause an alarming distortion of bone
- Not a true cyst because the bony cavity is usually filled with reddish-brown liver like tissue that fills with blood upon exploration

Front 22

Static bone cyst characteristics and treatment

Back 22

aka Stafne Defect
- Well demarcated radiolucency located inferior to mandibular canal containing submandibular gland
- No expansion of cortical plate and no treatment is required

Front 23

Dermoid Cyst characteristic and histology

Back 23

Benign cystic form of teratoma in the anterior floor of the mouth
- Contains epidermis and cutaneous appendages such as sebaceous/sweat glands, and hair follicles
- Well encapsulated with orthokeratinized stratified squamous epithelium and filled with a cheesy material
*- In the absence of skin appendages, the term epidermoid cyst is used

Front 24

Branchial Cleft Cyst characteristics and histology

Back 24

- Derived from epithelial remnants of branchial clefts which become entrapped within cervical lymph nodes
- Majority of cysts arise from second branchial arch and located on the lateral portion of the neck along the anterior surface of the Sternomastoid
- Histology shows lymphoid tissue and keratinacious debris in the cyst lumen

Front 25

Oral lymphoepithelial cyst characteristics, histology, and special

Back 25

aka Pseudocyst of oral tonsil
- Generally a soft tissue cyst in the anterior floor of mouth
- Histologically demonstrates abundant lymphoid tissue in cyst wall

- Lymphoepithelial cysts in the Parotid are often seen in HIV patients. Bilateral lymphoepithelial cysts are highly suggestive of HIV infection in a patient

Front 26

Thyroglossal Tract/Duct cyst

Back 26

Most common developmental cyst of the neck
- Numerous epithelial remnants from the thyroglossal duct and may be located anywhere in midline from foramen cecum to thyroid gland

Front 27

Antral Pseudocyst

Back 27

Dome shaped radiolucent lesion arising from the sinus floor
- Thought to be caused by pressure of accumulated inflammatory exudates under the sinus mucosa
- Occurs in 5-10% of population and do not require treatment